The danger I see immediately ahead is that interpretation of our laws depends heavily on precedent. If we play along to placate those with the loudest, most belligerant voices, we may set a terrible precedent that will come back to haunt us. We are, as I see it, at a crossroad. Do we want to maintain separation of legislative and executive branch powers?, or do we want to vest legislative power in the Executive?
For me personally the answer to that question is clear. So I see it as a matter of survival of the present Republic that the Executive not be allowed to subsume power given by the Constitution only to the legislative branch. If we to allow the President to circumvent the legislative branch solely because the legislature will not give him what he wants, regardless of his arguments, then the President must not, I would think, be allowed to turn the Constitution on its head by declaring an "Emergency". If the legislative branch determines that no true emergency exists, they must block the President's order so as not to set a precedent that might ultimately bring down the republic by subterfuge.
In a true emergency, the legislative branch has not time enough to react, and under those circumstances the President is authorized to take actions and assume responsibilities that are normally given only to the legislative branch. If there is time for Congress to block the Presidents "emergency order," then by definition, no true emergency exists.
No law exists that would allow the President to declare an emergency with regard to the Southern border, regardless of the facts on the ground. The Congress has had years to react legislatively to illegal and legal immigration via our Southern Border. It has done so as it saw fit. Even in the present manufactured crisis, the Congress has had many months to react. That certainly does net meet any definition of the word "emergency."
Do you recall that story of Franklin, possibly apocryphal? He was supposedly asked, " What kind of government is the new nation to have?" He responded, " A Republic Madame, if you can keep it."
"The brevity of that response should not cause us to under-value its essential meaning: democratic republics are not merely founded upon the consent of the people, they are also absolutely dependent upon the active and informed involvement of the people for their continued good health.These are words for all Americans to make note of in this time when the survival of our Republic is being challenged." -- Richard Beeman, Professor of History, University of Pennsylvania
Trump may have already been advised his declaration will not ultimately stand up. However, it appeared Trump was out of options to “save face” politically. At least now, he may have a chance to blame others for his failure to deliver on the wall after showing he “tried”.
Our courts are part of our checks and balances and will likely follow our Constitution and precident over any political philosophy the justices may personally have. I’m sure they would take a dim view of any politician attempting to mess with the DNA of our country.
Edit: Instead of messing with the DNA of our country, my post should read “Inappropiate use of executive power”.